Hitachi NJI-350B - Manual (Page 31)

Chapter 3 Function and Performance Specifications
3-15
3.3.12 Clock Function
23-point and 28-point types have calendar function. This can be operated either by internal output area or task code.
* 10-point and 14-point types do not have this function.
(1) Reading the clock data
By turning on the read request (R7F8), the clock data is read out in the reading value area (WRF01B to WRF01F).
(2) Writing the clock data
By turning on the write request (R7F9), the clock data stored in writing value area (WRF01B to WRF01F) is written
to the current data area (WRF00B to WRF00F). If the data is wrong, error flag (R7BF) will turn on. If data is right,
clock data will be written and writing flag R7FB will turn off.
(3) Adjusting the clock data ± 30 seconds
By turning on the ± 30 seconds adjustment request (R7FA), one of the following operations is performed depending
on the second value:
• If the second digits are 00 to 29, the second digits are set to 00.
• If the second digits are 30 to 59, the minute is incremented by 1 and the second digits are set to 00.
(4) Special internal output definitions
• Operation bits
I/O number Name Description
R7F8 Request to read calendar and
clock data Calendar and clock data is read out to
WRF01B-F01F.
R7F9 Request to write calendar and
clock data Calendar and clock data in WRF01B-F01F is
written to the current data in WRF00B-F00F.
R7FA Clock ± 30 seconds adjustment
request
Sets the second digits of the RTC to 00.
R7FB Calendar and clock setting data
error Turns on when the setting data is abnormal.
• Current data monitor area : Current data of the clock given always (all BCD data).
I/O number Name Description
WRF00B Year 4-digit year [yyyy]
WRF00C Month and date [mmdd]
WRF00D Day of the week 0 to 6 : Sunday to Saturday
WRF00E Hour and minute [hhmm] (24-hour system).
WRF00F Second [00ss]
• Reading/writing area : Clock data to be read or written.
(All BCD data)
I/O number Name Description
WRF01B Year 4-digit year [yyyy]
WRF01C Month and date [mmdd]
WRF01D Day of the week 0 to 6 : Sunday to Saturday
WRF01E Hour and minute [hhmm] (24-hour system).
WRF01F Second [00ss]
Note 1: The day of the week data is expressed as follows.
0: Sunday, 1: Monday, 2: Tuesday, 3: Wednesday, 4: Thursday, 5: Friday, 6: Saturday